DNA is the genetic material of all the living organisms except some viruses. Replication may be defined as the the biological process by which two daughter DNA are produced from the parental DNA strand.
Three important process of replication are initiation, elongation and termination. In initiation process, the DNA is unwind and enzymes are placed at the ori site. During elongation, DNA polymerase synthesizes the DNA strand from 5' to 3' direction. A termination site in the DNA results in the termination of DNA replication.
Thus, the new molecules of DNA in living cells are synthesized by DNA replication.
It begins with the unzipping of the double helix by
helicases. Unzipping forms y-shaped replication forks
exposing promoter regions (TATA regions) where the initiator proteins and factor bind to
the regions of DNA. A primer also
attaches to the region. DNA polymerase then
binds to the regions and begins adding DNA nucleotides
to the 3’ end of the primer based on the nucleotides on the template strand. Topoisomerase continues to unwind the DNA as the
polymerase progresses to the end of
replication.
